MILWAUKEE (CBS 58) — Late Friday, July 17, the Milwaukee city attorney announced the city intends to enforce its ban on federal law enforcement officers wearing masks during operations.

It's the latest move in a tense back-and-forth centered on immigration enforcement.

The Department of Justice insists banning masks puts officer safety at risk. But the city attorney wrote it does not accept that argument.

The latest move has the potential to set up a showdown between local police and federal agents.

Milwaukee City Attorney Evan Goyke wrote in a five-page response to the DOJ that Milwaukee will prosecute federal agents who violate the ordinance.

One week earlier, the DOJ wrote to the city requesting that federal officers be exempt from the mask ban.

"The mask ban threatens the safety of federal officers and their lawful operations," the assistant U.S. attorney general wrote.

The DOJ argued exposing officers' identities leads to "increasingly common threats of targeted harassment, tracking, interference, and assaults."

But as the number of ICE operations in Milwaukee increased in June and July, so did concerns over transparency and accountability.

The city's letter says videos showed agents, often unidentifiable, pulling people from vehicles.

"The city and the public have a right to know if masked, armed, and unidentified men seizing people on our streets are who they say they are," Goyke wrote.

Under federal policy, wearing a mask and displaying identifying information are left to the discretion of individual officers.

But the city argues, "Discretionary masking and identification are not essential to the functions of federal immigration officers."

The city also pointed to recent operations in Milwaukee involving some unmasked officers, saying that fact "undermin[es] any claim that masks are essential."

The letter adds, "If masking and identity concealment are essential, why would the federal government leave this up to the discretion of the individual officer?"

Goyke said federal officers will not be exempt from the mask ban, creating the possibility that Milwaukee police officers could be tasked with issuing citations to federal agents.

"And we will prosecute properly cited offenders," Goyke wrote.

The letter was released just before the close of business Friday, making it difficult to get immediate reaction.

The leader of immigration advocacy group Forward Latino said the organization fully supports the city's position.

Requests for comment from the Milwaukee Police Department and the Milwaukee Police Association had not been returned as of Friday evening.